1. Technical Field
The present disclosure relates generally to a lightning surge protection apparatus, and more particularly to a modular lightning surge protection apparatus.
2. Description of Related Art
With science and technology progress, the electric appliance products or the electronic products are increasingly precise. Hence, the surge protection and avoidance have become important topics. There are two main reasons of generating surge: switch surge and lightning surge. The circuit internally generates surge which is mostly associated with the actuation of the circuit components, it is called the switch surge. In addition, the circuit externally generates surge which is indirectly or directly caused by lightning strikes, it is called the lightning surge. Whether the switch surge or lightning surge, the light impact is to cause circuit malfunction and shorten the life of electronic components and the heavy impact is to cause circuit instantly overload and even burned. Therefore, a surge protection mechanism is essential besides the avoidance of generating surge.
Most of the industry commonly use surge prevention components to absorb or release the received surge energy. The more common components are metal oxide varistor (MOV) and gas discharge tube (GDT). The MOV is usually sintered by metal oxides such as zinc oxide and bismuth oxide. The MOV is also referred to as the surge absorber. The surge absorber has the nonlinear characteristics of high resistance value in low voltage and low resistance value in high voltage. In addition, the surge absorbers have different valve resistances according to their different proportion and composition of materials. The resistance of the surge absorber drastically reduces when a voltage difference is greater than the valve resistance, thus causing the massive current flow to inrush. Accordingly, the surge energy can be rapidly brought into the surge absorber so as to protect other electronic components from the surge. The gas discharge tube is internally filled with inert gas for discharging. Also, the surge energy in the GDT is released by the inert gas and converted into the thermal energy. Accordingly, the surge energy can be rapidly brought into the GDT so as to protect other electronic components from the surge.
Reference is made to FIG. 1 which is a perspective schematic view of prior art surge protection element with a coating layer. As mentioned above, the metal oxide varistor is usually used to provide the lightning surge protection. It is assumed that a first metal oxide varistor 101A, a second metal oxide varistor 102A, and a third metal oxide varistor 103A are applied to a single-phase three-wire power system with a line, a neutral, and a ground. Also, the amount of the metal oxide varistor is determined depending on different protection operations of the circuit, but not limited. Especially, each of the metal oxide varistors 101A˜103A is coated with a coating layer 111A˜113A of epoxy resin material. Also, each of the metal oxide varistors 101A˜103A is individually inserted on a printed circuit board (PCB) 30A. Accordingly, the metal oxide varistors 101A˜103A and other circuit elements form the lightning surge protection structure. However, the whole printed circuit board 30A (including components mounted thereon) must be discarded and replaced once any one metal oxide varistor is damaged. Hence, the prior art surge protection circuit has the disadvantages of larger occupied space, more complicated manufacturing process, and higher costs.
Accordingly, it is desirable to provide a modular lightning surge protection apparatus to integrate surge protection elements, temperature fuses, and jumper elements to form a small-scale modular circuit integration structure to provide the lightning surge protection.